BRISBANE, June 11 - It comes as Treasurer Jackie Trad prepares to hand down her first budget on Tuesday, the first of the Labor Government's second term.

The school money will be allocated over two years, starting next year, to ensure high schools will be ready for six full year levels for the first time in 2020.

With Year 7 now moved from primary to high schools, more room is needed to accommodate around 17,000 extra students.

More than 60 high schools across the state have been earmarked for the funding.

The investment comes as the government tries to juggle big spends on the health and infrastructure sectors with managing the state's debt, which is set to hit $83 billion in the next few years.

Trad insisted she would post a surplus when the budget is handed down on Tuesday.

"Our track record over the last three years has seen debt come down from record highs under the LNP, and we will continue to pay down debt and manage our economy," she told reporters on Monday.

Trad argued the actual debt figure was closer to $30 billion, because that was government debt, not the extra debt incurred by government-owned corporations like power companies.

The government has already revealed health spending will rise by almost $800 million from last year to a record $18.3 billion.

There will also be a $45 billion spend on infrastructure - levels not seen since the 2011 flood recovery.

The government will pay for its programs and pay off its loans by introducing five new taxes, mostly targeting the top end of town.

The new taxes hit the owners of luxury cars, and there's a new land tax category for large holdings, higher stamp duty for foreign buyers of property, as well as a new betting tax targeting agencies based outside the state.

The government will also introduce a $70-per-tonne waste levy which is predicted to raise around $200 million a year.